<!DOCTYPE html>
<html>

<head>
<meta charset="UTF-8">
<title></title>
<script src="js/UnicodeAnsi.js" type="text/javascript" charset="utf-8"></script>
<script type="text/javascript">
	
var keyStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
// 将Ansi编码的字符串进行Base64编码
function encode64(input) {
	var output = "";
	var chr1, chr2, chr3 = "";
	var enc1, enc2, enc3, enc4 = "";
	var i = 0;

	do {
		chr1 = input.charCodeAt(i++);
		chr2 = input.charCodeAt(i++);
		chr3 = input.charCodeAt(i++);

		enc1 = chr1 >> 2;
		enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
		enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
		enc4 = chr3 & 63;

		if(isNaN(chr2)) {
			enc3 = enc4 = 64;
		} else if(isNaN(chr3)) {
			enc4 = 64;
		}

		output = output +
			keyStr.charAt(enc1) +
			keyStr.charAt(enc2) +
			keyStr.charAt(enc3) +
			keyStr.charAt(enc4);
		chr1 = chr2 = chr3 = "";
		enc1 = enc2 = enc3 = enc4 = "";
	} while (i < input.length);

	return output;
}

// 将Base64编码字符串转换成Ansi编码的字符串
function decode64(input) {
	var output = "";
	var chr1, chr2, chr3 = "";
	var enc1, enc2, enc3, enc4 = "";
	var i = 0;

	if(input.length % 4 != 0) {
		return "";
	}
	var base64test = /[^A-Za-z0-9\+\/\=]/g;
	if(base64test.exec(input)) {
		return "";
	}

	do {
		enc1 = keyStr.indexOf(input.charAt(i++));
		enc2 = keyStr.indexOf(input.charAt(i++));
		enc3 = keyStr.indexOf(input.charAt(i++));
		enc4 = keyStr.indexOf(input.charAt(i++));

		chr1 = (enc1 << 2) | (enc2 >> 4);
		chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
		chr3 = ((enc3 & 3) << 6) | enc4;

		output = output + String.fromCharCode(chr1);

		if(enc3 != 64) {
			output += String.fromCharCode(chr2);
		}
		if(enc4 != 64) {
			output += String.fromCharCode(chr3);
		}

		chr1 = chr2 = chr3 = "";
		enc1 = enc2 = enc3 = enc4 = "";

	} while (i < input.length);

	return output;
}
var strEncode = encode64(strUnicode2Ansi("我是中国人"));
console.log(strEncode);
var str=strAnsi2Unicode(encode64("我是中国人"));
console.log(str);
</script>
</head>

<body>
</body>

</html>